Providing high-speed services with different Quality of Service (QoS) requirements to users is an active study area for the future-generation communication system. Especially, studies are being actively conducted on supporting high-speed services by ensuring mobility and QoS to broadband wireless access (BWA) communication systems such as wireless local area network (WLAN) and wireless metropolitan area network (WMAN).
In such a BWA communication system, a receiver, for example, a mobile station (MS) receives communication services with different QoS requirements from a serving base station (BS), including services of Unsolicited Granted Service (UGS), real time Polling Service (rtPS), non-real-time Polling Service (nrtPS), and Best Effort Service (BES) types.
The most fundamental issue to communication systems is how efficiently and reliably data can be transmitted with limited resources, such as channels. To meet the demand for a high-speed communication system that can additionally process and transmit video and radio data beyond early-stage voice service, a future-generation multimedia communication system, which has recently been studied actively, seeks to increase system efficiency by use of an appropriate channel encoding scheme.
Unlike a wired channel environment, errors are inevitable due to many factors, such as multipath interference, shadowing, propagation attenuation, time-variant noise, and fading in the wireless channel environment of a communication system. The resulting information loss severely distorts transmission data, thus degrading the overall performance of the communication system. To reduce data loss and increase system reliability, error control techniques are used according to channel characteristics. A basic error control technique is to use an error correction code.
To provide communication services with various QoS levels, such as services of the UGS, rtPS, nrtPS, and BES types to users, the BWA communication system should transmit data to mobile stations without error-caused loss in a radio channel environment inherent to the communication system. However, there are no specified schemes for providing communication services with QoS ensured to users. Thus, there exists a need for a method for providing communication services with various QoS requirements to users, that is, transmitting and receiving data of various service types.